Desarrollador prueba extendida

A social media application uses the AWS SDK for JavaScript on the frontend to obtain user credentials from AWS STS. The application stores assets in an S3 bucket and serves them through a CloudFront distribution. The credentials for the assumed role are stored in plaintext in a JSON file within the application code. Which solution will allow the application to retrieve user credentials without hardcoding them?

• Add a LambdaEdge function to the distribution; invoke it on viewer request; grant its role permission to access AWS STS; move all SDK calls into the function.
• Add a CloudFront function to the distribution; invoke it on viewer request; grant its role permission to access AWS STS; move all SDK calls into the function.
• Add a LambdaEdge function to the distribution; invoke it on viewer request; move credentials from the JSON file into the function; move all SDK calls into the function.
• Add a CloudFront function to the distribution; invoke it on viewer request; move credentials from the JSON file into the function; move all SDK calls into the function.

A developer is creating a Lambda function that retrieves data from a third‑party system, formats it into a PDF, and encrypts the file using AWS KMS. The PDF file can exceed 1 MB. Which step must be taken to ensure that the encryption can be reversed later?

• Store the encrypted data key from GenerateDataKey along with the encrypted file.
• Store the plaintext key from GenerateDataKey on disk.
• Use the plaintext key with the KMS Encrypt API to encrypt the file.
• Use the encrypted key with the KMS Encrypt API to encrypt the file.

A developer wants to reduce risk when deploying a new version of a Lambda function by splitting traffic between the existing version and the new version.

• Configure a weighted routing policy in Route 53 to split traffic between the versions.
• Create a Lambda function alias that splits traffic between the two versions.
• Create an Application Load Balancer (ALB) that splits traffic between the two versions.
• Create a new Lambda function that filters requests and invokes the appropriate version based on content.

A developer is designing a serverless multi‑tier application for a game. The application must allow users to register and log in via a web browser and make requests to Lambda functions behind an API Gateway HTTP API. Which solution meets these requirements with minimal operational overhead?

• Create Amazon Cognito user pools to integrate with external social identity providers and configure IAM roles for identity pools.
• Program the sign‑in page to create IAM groups and assign roles.
• Create an RDS for SQL Server database to store user credentials and manage access.
• Configure the sign‑in page to store users in a DynamoDB table with an attached IAM policy.

A developer is building a cloud‑based photo storage application for mobile users that supports tens of thousands of users. The application uses an Amazon API Gateway REST API integrated with AWS Lambda functions to process photos and stores photo metadata in Amazon DynamoDB. Users must sign up, upload photos (300 KB to 5 MB), and retrieve previously uploaded images. Which solution minimizes operational overhead?

• Use Amazon Cognito user pools for user account management, set up an API Gateway Cognito authorizer, and have the Lambda function store both photos and metadata in DynamoDB, retrieving photos directly from DynamoDB.
• Use Amazon Cognito user pools for user management, configure an API Gateway Cognito authorizer, and have the Lambda function store photos in Amazon S3 while saving the S3 object key in DynamoDB for metadata; retrieve photos by querying DynamoDB for the key.
• Create an IAM user for each application user during sign‑up, use IAM authentication with API Gateway, and use the Lambda function to store photos in Amazon S3 while saving the S3 key in DynamoDB; retrieve photos by querying DynamoDB.
• Create a DynamoDB table for user accounts, implement a Lambda authorizer to validate credentials against it, integrate it with API Gateway, and have the Lambda function store photos in Amazon S3 while saving the S3 key in DynamoDB; retrieve photos by querying DynamoDB.

A developer supports an application that uses a DynamoDB table. The table stores customer orders, and the application must perform an operation to retrieve multiple items with a minimum impact in database. Which DynamoDB API call is most efficient for this purpose?

• BatchGetItem.
• GetItem.
• Scan.
• Query.

A developer is creating an application that stores sensitive data in a DynamoDB table. The table is configured to send change events to a DynamoDB stream, which triggers a Lambda function to process incoming orders. An operational review reveals that some orders have a quantity of 0. The developer needs to create a dashboard showing the number of unique customers affected per day. Which solution meets these requirements?

• Grant the Lambda function permission to send logs to CloudWatch Logs; implement a CloudWatch Logs Insights query that counts unique customers for orders with quantity 0, grouped by day; add the query to a CloudWatch dashboard.
• Use Amazon Athena to query CloudTrail logs for API calls and build a dashboard.
• Configure the Lambda function to send events to EventBridge; create a rule to group unique customers and output to a dashboard.
• Enable custom CloudWatch metrics for the DynamoDB stream; create an alarm that groups unique customers; add the alarm to a dashboard.

A developer's AWS Lambda function generates temporary files (less than 10 MB) that are accessed and modified during execution and do not need to be stored permanently. Where should these temporary files be stored?

• In the /tmp directory of the Lambda execution environment.
• On Amazon Elastic File System (EFS).
• On Amazon Elastic Block Store (EBS).
• On Amazon S3.

A company uses Amazon Cognito user pools with MFA to secure user records and requires that an email notification be sent for every login. Which solution is the most operationally efficient?

• Develop a Lambda function using Amazon SES to send email notifications, invoked via an API Gateway endpoint triggered by the client upon login confirmation.
• Develop a Lambda function using Amazon SES and attach it as a Cognito post‑authentication trigger to send email notifications.
• Develop a Lambda function using Amazon SES and set up a CloudWatch Logs subscription filter to trigger it based on login events.
• Configure Cognito to stream logs to Kinesis Data Firehose and use a Lambda function to process the logs and send email notifications.

A company migrated its application to EC2 instances. Although the UI scales well, the shipping request process is encountering duplicate, lost, and out‑of‑order requests. Each shipping request is <250 KB and takes 5–10 minutes to process. The solution must ensure that each request is processed exactly once and in order, without modifying the legacy system.

• Use a Kinesis Data Firehose delivery stream and a Kinesis data stream; modify the application to write to the stream.
• Use a Lambda function triggered by an SNS topic to process requests.
• Use a Lambda function triggered by an SQS standard queue; modify the application to write to the queue.
• Use a Lambda function triggered by an SQS FIFO queue; modify the application to write to the FIFO queue.